Toshiba Q9 Plus ASD, Installation & Operation Manual

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14 Q9 Plus Bypass ASD/Bypass Box Installation and Operation Manual
The three positions of SW2 ( Off , INV , and BYP ) are described below.
Off — K2 and K3 remain in the normal state.
INV — Energizes K2 which turns off LED 1 (Test Mode) (if on), illuminates LED 2 (INV Mode),
opens K2 at Stage 3, closes K2 at Stage 4, and completes the ST terminal path via PCB 11. The
resulting closure of K2 at Stage 4 energizes the 2M contactor (jumper or open-damper signal at DRA/
B required), which allows the ASD output to be applied to the motor (see 2M at Figure 7 on pg. 31 ).
BYP — Energizes K3 which turns off LED 2 (INV Mode) (if on), illuminates LED 3 (Bypass
Mode), opens K2 at Stage 4 (which opens 2M if closed), and closes K3 at Stage 4. The resulting
closure of K3 at Stage 4 energizes the 3M contactor (jumper or open-damper signal at DRA/B
required), which allows the utility power to be applied directly to the motor bypassing the ASD (see
3M at
Figure 7 on pg. 31 ).
Note: Ensure that the phase relationship of the L1 , L2 , and L3 connections to the motor for
the Bypass mode of operation and for the ASD-driven operation are consistent. The
Reverse and Forward functions will be reversed if not properly connected (see
diagram in Figure 7 on pg. 31 ).
The Damper Response feedback circuit (DRA/DRB) may be used to prevent a motor from attempting
to force air flow through a duct that has a closed damper.
Damper motor power (120 VAC) is provided from an external source and is applied via the switched
DSA/DSB circuit ( OUT1 contacts). The 120 VAC is switched via the OUT1 contacts while operating in
the INV mode or switched via the K3 contacts while operating in the Bypass mode.
Note: OUT1 contacts are labeled DSA and DSB on the Terminal Board .
Stage 4 Function
In the INV mode, the OUT1 closure (set to Damper Command) occurs upon receiving a Run command
and allows power to be applied to the damper motor. Once the damper-mounted DRA -to- DRB contacts
are closed (open damper required), K4 is energized.
LED 4 (System Interlock) illuminates and the K4 contacts close the S3 -to- CC connection ( JP1 jumper
required), completing the Damper Feedback circuit requirement for ASD operation. The DRA -to-
DRB closure also provides power to the 2M coil allowing for the ASD output to be applied to the motor
while operating in the INV mode.
If no discrete input terminal is assigned the function Damper Feedback, this permissive
will not be a requirement for normal system operation.
With all other permissives configured to run, the motor will run without activating a
Damper Feedback discrete input terminal.
In the Bypass mode, K3 is energized via SW2 . The K3 contact closure at PCB 11 applies power to the
damper motor ( Terminal Board jumpers JPDS1 and JPDS2 are required). Once the damper-mounted
DRA -to- DRB contacts are closed (open damper required), the 3M coil is energized and provides utility
power to the motor, bypassing the ASD.
The DRA -to- DRB contacts are provided via a reversible damper-mounted switch. The switch
terminates power to the damper motor once the damper is fully opened or closed (reversible means that
only the opposite function is available once reaching the fully opened or closed position).